Attaining the required evenness of pavement surfaces has long involved a tedious and time-consuming process. Standards have been set by Federal and State authorities, prescribing specific requirements as to the surface evenness. A typical standard permits a surface tolerance wherein no high spots of more than 1/8 inch exist beneath a 10 foot straightedge. Any surface exceeding this range must be corrected and the usual procedure is to utilize an apparatus including one or more grinding drums or heads suitable for cutting away the raised spots in the material of the pavement, such as concrete.
Examples of prior apparatus for accomplishing the above operation will be found in U.S. Pat. Nos. 3,703,316 and 3,771,831 issued to Hatcher et al, on Nov. 21, 1972 and Nov. 13, 1973 respectively. These patents show rotary cutter assemblies carried by a frame and which are manipulated by means of fluid cylinders. The frame is adapted to be propelled, as an intermediate component of a tractor-trailer rig.
The need exists for a relatively compact and economical apparatus for the grinding of pavement and which allows precise control of the cutting action so as to properly remove only those raised areas which have been previously marked by the appropriate officials.